This invention relates generally to shoes and more particularly to shoes that can extend and retract spikes from the soles to enhance traction.
Use of cleats on the bottom of shoes to enhance traction has been known for a long time. Where the wearer may need to support his entire body weight during the activity, long cleats project from the bottoms of the shoe. Such cleated shoes are used in climbing activities such as mountain climbing, hiking, lumber and telephone pole scaling.
Cleated shoes are also used on open ground or artificially-turfed surfaces for athletics and sports activities, e.g., football, baseball, soccer, to help enhance traction during running and turning. The cleats also act to help anchor one's footing when the wearer is trying to maintain a stationary position e.g., swinging a golf club or baseball bat or blocking an opponent with one's body during a football game.
Cleated shoes are also used on surfaces exposed to the elements where ice and snow may form and the wearer wants to avoid slipping or sliding when walking.
Some cleated shoes function solely for the purpose of preventing the heel or sole from wearing down during use; i.e., because the cleat projects outward from the sole, the cleat engages the ground during wear instead of the sole or heel.
However, it is also desirable to be able to eliminate the cleats once the need for them is gone, e.g., when the wearer enters an enclosure that has a floor where the cleats are no longer needed and may even damage the floor once the wearer walks on this surface with the cleats projecting. The solution has been to make such cleats either removable or retractable so that the wearer can wear the shoe in almost any environment and can control when the cleats will or will not project from the sole.
The following constitute examples of various types of prior art retractable cleat shoes found in the following U.S. Pat. Nos.: 48,943 (Hodgins); 264,105 (Rust); 1,071,147 (East); 3,343,283 (Henry); 3,716,931 (Loudermilk); 3,793,751 (Gordos); 4,375,729 (Buchanan, III); 4,825,562 (Chuang); 4,821,434 (Chein) .
The apparatus disclosed by Hodgins is a device embedded within the heel of a shoe that the wearer can manually adjust to compensate for any worn-down portion of the heel and maintain an even heel. The device uses two horizontally sliding surfaces with corresponding sawtooth edges to regulate the amount of cleat projection necessary to maintain heel height. With the cleats entirely recessed in the heel, the two horizontal surfaces' teeth members fit securely together. As the upper horizontal surface is pushed out of alignment with respect to the lower surface, the lower surface is driven downward by the upper surface teeth. The amount that the lower surface is driven downward corresponds to the amount of cleat projection. Two screws protruding from the front of the heel adjust the height of the cleat and lock the cleat in place respectively.
The apparatus disclosed by Rust is also a device embedded in the heel but is used to provide better traction on the ice. The device also uses two horizontally sliding surfaces with a ratchet surface interface to drive the cleats in or out of the heel. There is no adjustment of the cleat height since it is either recessed within the heel or projecting out from the heel. The Rust apparatus is controlled by a projecting bar that is directly attached to the upper surface. The wearer can strike the cross-sectional end of the bar against any hard surface to either project the cleat (and thereby lock the cleat in place) or unlock the cleat (and thereby retract the cleat into the heel).
The apparatus disclosed by East is a device that uses an "L-shaped" pivoting member to act as both a cleat and as a cover to prevent foreign matter from entering the aperture from which the cleat emerges. The East device is disposed within the heel of the shoe and uses several overlaid plates with apertures through which the "L-shaped" members pivot. By manipulating the several plates with respect to one another using a sliding tab protruding from the heel, the "L-shaped" member pivots about its corner. With the tab pushed to one extreme setting the cleat is locked in a downward position while the aperture from which it came is covered by the other portion of the "L-shaped" member. Pushing the tab to the other extreme position pivots the cleat upwards into the apertures with the cleat itself now acting as a cover to prevent foreign matter from gaining access into the apertures.
The device disclosed by Henry is a retractable antislip device for shoe heels also. A torsion spring/flange assembly is embedded in the heel and is activated by a key inserted into a cavity within the heel. Turning the key in one direction forces two cleats to emerge from the heel and are thereby locked into position by a trapped crank arm within a groove while torsioning the spring. Turning the key in the other direction removes the crank arm from the groove and the spring becomes unloaded as the crank arm is pulled upwards by a retraction flange and thereby retracting the cleats into the heel.
The device disclosed by Loudermilk is a retractable cleat assembly, a multitude of which, are mounted within a base that is then attached to the sole of a golf shoe, including the golf shoe heel. The retractable cleat assembly design utilizes a cleat that pivots within a rectangular receptacle. With each receptacle mounted in the sole and the shoe turned over, the cleat remains in a retracted state. A receptacle cover, with a hole that allows the extended cleat to protrude from, fits snugly over the receptacle to prevent foreign matter from entering the receptacle once the cleat is in an extended state. When the cleat is in a retracted state, a small plug fills the hole in the cover to keep out foreign matter. To extend the cleat, an independent magnet- formed into a "U" shape to permit the protruding cleat to pass between the two sides of the magnet when it lies flush with the receptacle cover- is brought into contact with the metallic receptacle cover. As the magnet/cover assembly is removed from the receptacle, the metallic cleat is attracted from its retracted position within the receptacle and pivots into its fully extended position. The magnet/cover assembly is then pressed back onto the receptacle, with the cleat passing through the hole in the cover and between the magnet's two sides. The magnet is then removed from the cover and this procedure is repeated for each retractable cleat assembly. To retract the cleat, the cover is pulled off from receptacle and the cleat is forced down into the receptacle. The cover is then forced down over the receptacle and the small plug is inserted to close off the cleat hole in the cover. A multitude of these retractable assemblies are permanently mounted in as many layers of sole material as necessary to yield sufficient cleat penetration into the ground when extended. These sole layers are themselves then permanently mounted to the shoe sole.
The device disclosed by Gordos retracts or extends cleats from a golf shoe by means of a protruding knob at the heel of the shoe which rotates a flexible cam shaft that runs longitudinally within the sole of the shoe. The flexible cam shaft allows the use of a shaft from toe to heel within a shoe while not relinquishing the shoe's usual contour of the foot arch. A plurality of cleats are mounted in a cleat plate that moves up and down within a space within the shoe sole. Straps are mounted to the cleat plate which pass over the cam shaft at specific locations. When the knob is rotated, a cam- located on the shaft where these straps are mounted- engages the strap and thereby lifts or releases the strap causing the cleat plate to either retract or extend the cleats respectively.
The device disclosed by Buchanen III allows the control of cleats emanating from sole of the shoe to be accomplished without the use of an external controlling mechanism, i.e., the control mechanism is also embedded within the shoe. The cleats are mounted to a flexible material that forms a snug fit with the tread material. The tread material contains several apertures through which the cleats emanate. A sliding cam member presses the flexible material against the tread surface forming a watertight seal so that any foreign matter that enters the aperture within the tread has no access within the shoe. The cam member is designed such that it normally "dimples" the flexible material where a cleat is attached and thereby the cleats are held in a recessed position. When the cam member is driven backward, it presses down on the flexible material forcing the cleat out through the tread aperture, thereby extending the cleat. The cam member locks in that position and thereby closes off the aperture from any foreign material while locking the cleat in an extended position. Sliding the cam member forward causes the flexible material to "dimple," thereby retracting the cleats while maintaining a snug fit with the tread and thereby preventing foreign matter from getting into shoe. The cam member is controlled by two springs mounted perpendicular to one another within the heel. The springs are locked when associated slide members engage internal grooves. Pressure applied to the back right side of the shoe locks and unlocks the springs to achieve cleat retraction or extension.
The device disclosed by Chuang allows for the extension or retraction of elastic cleats from a shoe to be used on the ice and snow by turning a key accessed from within the shoe itself. There are two independent nail sets, a group of cleats that are mounted to a common member, in the front and heel of the shoe. Each nail set is normally positioned in a retracted position, with the cleats aligned with holes in tread from which the cleats will protrude when extended. A sliding member, when driven backward toward the heel, forces each nail set downward causing them to extend and to be locked in that position. The sliding member is controlled by a disk mounted inside the shoe and covered by the insole. On the underside of this disk is a pin that fits within a slot in the sliding member. When the disk is rotated, the pin forces the sliding member either backward or forward, depending in which direction the disk is rotated. A backward movement forces the nail sets downward, extending the cleats; a forward movement removes the downward force and permits the cleats to be pushed up into the sole of the shoe unopposed. To rotate the disk, the wearer must remove the shoe and then remove the insole thereby uncovering the disk.
The device disclosed by Chein is a shoe structure with nails to extend or retract in by kicking forwards or backwards. This device combines the Hodgins and Rust teachings of sliding members that force the cleats out when two surfaces slide with respect to one another; this device also incorporates the Buchanan III teaching of having no external member controlling the retraction/extension functions. In the Chein device, the wearer simply kicks the toe of the shoe against a hard surface to extend the cleats while kicking the heel against a hard surface to retract the cleats.
Although much of the discussed prior art concerns cleats that move vertically, i.e., up for retraction and down for extension, such prior art does not disclose means and methods for easily and effectively covering up the cavity remaining in the shoe tread when the cleat is retracted. Moreover, a means to keep dirt, ice, water and other foreign matter out of the cavities from which the cleat emerges and into which they recede is lacking in the prior art except for the East patent provides a method for covering the aperture once the cleat is retracted. However, East's device and method of operation does not simultaneously cover all cleat apertures throughout the entire length of the sole. Rather, the East disclosure is restricted to transversely-located, rotatably retractable heel cleats.
Many of these retractable shoe designs make the shoes heavy to wear or are bulky.
Two of these of shoe devices require the removal of the shoe in order to retract or extend the cleats.